Internal-combustion engine



May 8, 1928. 1,668,737

D. MC. SHANNON INTERNAL COMBUSIVION ENGINE Filed Jan; 31. 1922 5Sheets-Sheet l May s. 1928.

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D. McC. SHANNON INTERNAL COMBUSTION ENGINE Filed Jan. 31, 1922 5Sheets-Sheet 3 N N Y l' fbffun WAM/QmumJL/ 5 Sheets-Sheet 5 i MNE/vree:DAVID M( C. SHANNON,

May 8, 1928.

D. McC. SHANNON INTERNAL coMBUsTIoN ENUM-1 Filed Jan. s1, 1922 PatentedMay 8, 1928. f

i UNIT-EDSTATES j 1,658,731 PATENT. OFFICE.

j DAvID MccRoRiE SHANNON,` QFIDIBKENHAD, ENGLAND.

INTERNAL-COMBUSTION ENGINE.

Application ined January s1, maa-serial No.

This invention relates to internal combustion engines, and has referencemoreparticularly to apparatus for 4the injection of liquid fuel ininternal combustion engines 5 of the type in which the fuel is injectedby means of a, blast of air or other gas obtained from the Workingcylinder of the engine; and the object of the invention isto rovideapparatus forthis purposevvhich s iall i a separate compressor` have notbeen suo-` cessful because the compressor, designed to give the finalpressure, has had to deal with gases of such` high initial temperatureas to make successfullubrication impossible, thus rendering theworkingof Lthe, compresser .piston and valves uncertain,v and their workinglife of `comparatively short duration.

`According Vto the present invention, the

3U gases t-aken,at the appropriate `part of the cycle, from 1 theWorking cylinder of. the

engine, are discharged therefrom through a cooling device interposedbetween the Working cylinder and a comparatively small compressor usedto givethe final compression; this cooling device comprises iuid cooledheat exchanging surfaces, say one or more comparatively long small-boretubes so arj ranged that the gasespass therethrough 1n` 4u a thin streamor streamsto give` efficient cooling and to prevent the passage throughthe cooler to the compressor,of any liame or high temperature gasesfwhich Vwould cause i an explosion in the compressor, the comparativelylarge extent and--long length. of the heat exchanging surfaces of. thecooler in proportion tothe small cross-sectional area of thepassage-Ways for the gases thus ensuring immunity from explosion'in the`compressor, and maintaining a reasonably low temperature in the latter.i

Apparatus constructed yaccording to the invention kcompri`ses,a coolerto` cool the comparatively j high` temperature airy, or. other gasesWithdrawn from the working cylinder and before delivery thereof to the`533,132,`and in Great Britain February 3, 1921.

compressor.; a compressor for raising the pressure ofthe said airorgases to a suitable valve for injecting the fuel; a fuel supply pump;and a pulverizing chamber in which the air orother gas, after said finalcompression, is thoroughly mixedwith fuel supplied to the saidchamber,Which cha-mberis fitted With a nozzle or flame plate throughwhich the fuel sprayed by the compressed gases is injected intoptheworking cylinder ofthe engine.

. Preferably the same nozzle is used for the passageiof `the air orother gas" from the Working cylinder to ythe compressor cylinder,j andffor spraying ,the fuel into1 the .Working cylinder, thus dispensingwith the usual cam operated inwardly or outwardly openingvalve. Y h iAlternatively, the air or other gas may be taken from the cylinder byWay of a separate openingthrough the cooler, anonreturn valve being'located atthe endof the cooler remote from `the. `Working cylinder. Thefuel maybe introduced into the mixing chamber at any desired point inthe stroke, and'on the forward movement` of the compressor piston; iscarried With the` air into the Workingcylinder or the fuel may beinjected into the airstreainuby a fuel supply pump the plungerof` which`has a movement similar to and `synchronousWith that which operates thecompressor piston.`

The compressor may be integral with the `cooler or be separate from it,as may be most convenient, .and may be driven in any suitable manner bylevers, fluid pressure, or gearing from the engine.

The `invention is applicable generall to internal combustion engines thefue of which `is sprayed" into the working cylinders, and isparticularly applicable to `engines of this type having opposed pis-` ytons, say of the nou7 Well known Fulla ar type, and the invention vvill,in the first 1nstance, be described as applied to a Fullagar engine. j

In the preferred form, the cooler casing may be cylindrical and may bearranged coaxialflywith the fuel injectionnozzle which in the Fullagarengine fasses through the central zonel of the `cylin er liner, thecooler extendingacross the water jacket casing of the cylinder,in whichcase the compressor may be conveniently arranged asaco-axial eittensionofthe cooler. j

At the cylinder end the interiors of the los tubular cooling surfaces(which may be straight or curved small bore tubes the exteriors of whichare cooled by a suitable cooling fluid circulated through the cooler,)open into a pulverizing chamber leading to the injection nozzle, and atthe opposite end they open into the compressor cylinder. Fuel is led tothe pulverizing chamber through a fuel inlet nozzle which is preferablycentrally located and is provided with jets so disposed that when thecompressor makes its Working stroke and the gases are forced through theseveral cooling tubes across the pulverizing chamber, the fuel issuingfrom these jets is directed across the streams of gas so that the fueland gases are thoroughly mixed in the pulverizing chamber preparatory tobeing sprayed into the cylinder through the fuel injection nozzle.

The cooler may consist of one or more small bore tubes arranged in theWater jacket space of the main cylinder, thus dispensing With a specialcooling jacket round the tubes, or it may consist of a bent or straighttube or tubes, each tube being inside another tube of larger bore withthe Water circulating in its annular space between the two tubes, thelength of the tubes being sufficient to bring about the desired amountof cooling.`

The action of the apparatus is as follows:

As the air or gas is compressed, during the compression stroke, in theWorking cylinder, a portion of its passes through the tubular coolingsurfaces of the cooler into the compressor cylinder, the piston of whichis then forced to the end of its outstroke. At an appropriate period inthe cycle, the compressor piston is forced to the inner end of itsstroke, compressing the air or gas before it and discharging the saidgas through the cooler into the pulverizing chamber, Where it meets Withthe fuel then being sprayed from the fuel inlet nozzle and the mixtureof fuel and gas is then .sprayed into the Working cylinder through theinjection nozzle. The pump delivering fuel would usually have itsmovements co-ordinated with that of the compressor piston so that thefuel is delivered Vto the pulverizing chamber as the compressor pistonis making its working stroke.

In a modification, the air or gases passing from the Working cylinder tothe compressor pass through small bore cooling tubes as described, butadditional passage-Ways are provided through which the gases pass fromthe compressor to the pulverizing chamber; the ob'ect of providingadditional passagevWays or the return flow of the gases is to reduce theresistance as to flow and to reduce the degree of cooling of the gasesas they pass through the cooler after final compression.

A non-return Valve to open on the discharge stroke of the compressor isarranged at any convenient point in the additional passage Ways or Ways.

In a further modification, instead of small bore tubes to form the heatexchanging surfaces, pairs of concentric tubes may be arranged, thecooling fluid circulating through the inside of the inner tube andaround the outside of the outer tube, the air or gas to be cooledflowing. through the angular space between the tubes.

In a further modification, a cooler of any suitable type may be fittedto a port in the cylinder liner which is covered by the engine pistonwhen the latter is in its extreme inner position, the cooler leadingthrough a nonreturn valve to a receiver. When the said port is uncoveredby the piston, compressed air or gas is forced through the cooler,cooled therein, and discharged into the said receiver.V From thereceiver the air or gas is taken to a compressor' adapted to raise thepressure to that suitable for injection purposes through a fuel valveand injection nozzle of the ordinary type, the compressor for finalcompression bemg separately driven from the engine crank shaft or in anyother convenient manner.

Alternatively, the port may be `arranged without being covered bythepiston, the valve which is located at theend of the cooler remote fromthe combustion chamber being mechanically or otherwise operated to takethe air or gas from the Working cylinder when the Working pistons are inany desired position.

In the modifications described, it has been assumed that the compressoris of the single piston type, but With the object of relieving theapparatus and the part of the engine structure to which it is attachedof all or any part of the loads due to the operation of a singlecompressor piston, and also with a view to the employment of smallerpiston with `reduced lads,rthe compressor cylinder may be fitted With oposed pistons.

The compressor cylin er may be arranged so that the axes of its twobores in which the pistons'reciprocate are in the same line, or beoffset and parallel, or be inclined atany angle in the saine place, orin different planes, Bothpistons, or only one of them maybereciprocated, by any suitable means, so as to have a definiterelationship to the motion of the main piston or pistons in the workingcylinder. There one piston is reciprocated, the other may be preventedfrom moving axially by a pin jointed link, or other attachment to somepart external to the apparatus.

The compressor cylinder is in each case provided with a Water jacket.

In a convenient arrangement of the epposed piston type of compressor,the latter may be arranged symmetrically and translll) "verselyacrossthe end of the cooler` which* may be of any suitable type.

The passage-Ways traversed by the air or gases from the cooler to thecompressor may be fitted with retarders so as to increase the coolingeffect, and wire gauze rdia- *phragms maybe tted across the passage-Iway between they compressor and the pulverizing chamber so as toprevent the pasr sage of flame into the compressor.

As stated, the invention is applicable to .l

internal combustiony engines generally `and may be employed in suchengines using solid pulverized fuel ,the parts being modilied to suitany particular arrangement.

IVhaVe illustrated my invention in the accompanying drawings, in which:n

IFig. l is an elevation in conventional medial section and shows thepreferred arv rangement.

Fig. 2 1s a sectional elevation of a modi `lied construction of thecooler; the mode in which the cooler is fitted tothe working cylinder,and the mode in which the compressoris operated may be as shown in Fig.

` Fig. `2A is a: part` plan view of Fig. 2.

`Figs. B, t and 5 illustrate further modiiications of lthe cooler. Fig.3 being a View similar to Fig. 2, and being insection on the line III,III of Fig. 4, which is a plan View in section on the line IV, IV ofFig. 3.

Fig. 5 is a plan in `section on the line V, V7 of Fig. 3. Fig. 6 is anelevation in section of a further modification in which the cooler heattransmitting vsurface is located in the water-jacketsV space of theworking Vcylinder.'

Fig. 7 is'an elevation inf conventional medial sect-ion and shows amodification of the compressor andgeneral arrangement `particularlysuitable for an opposedpiston ftype of engine such as Fullagar engine. v

the `well known Referring first to'Fig. l,

A is the working cylinder of an internal combustion engine of say theFullagar type; w1 is the Water-jaeketof the cylinder, fr is the fuelinlet opening. B is the nozzle `through which the mixture of air and oilis sprayed into the Working cylinder. C is the fuel nozzle, throughwhich fuel is sprayed into the atomizing chamber D, E is the cooler, Fthe compressor and Grl the oil pump. Thecooler which is of cylindricalconfiguration `is arranged with its axis in line with a fuel inletopening, andthe compressorF is arranged in line with thecooler. Thecooler consists of a cylindrical casing e1 which is secured in positionin a cylindricalreces's in the working cylinder casing,

so that the atomizing chamber D is formed between the inner end of thecylindrical casing el and the air and oil nozzle B.

The `fuel nozzleC is fitted at the end of a eentral passage-Way 62, fromtheinlet e3 of which connection is made tothe oil pump G. The heatexchanging surfaces consist of i a number of small boretubes e* whichtraverse the annular space between the cylindrical casing el and thecentral stalk c in which the central port e2 `is formed. These "tubes etopen at one end into the atomizing chamber D and open at the other endinto the cylinderI space of the compressor F.

The cooling water is led from the workingcylinder jacket al through theopenings ai* fand e6 linto the annular space; it traverses this spaceand around the tubes e4, and flows thence through the connectingpassage-way e7 to the water-jacket f6 `of the eompressonand leaves bythe outlet f", or it may enter at f" andlow in the reverse direction tothat described.

The compressor may be of `any suitable type and may be operated in 'anysuitable manner. `In the example illustrated jfl' is the piston of thecompressor, the rod f5 of which is connected to a crossehead f2, the4latter being reciprocated by radius rods f `connected to a lever,operated say, by a cam. Gis t-he oil pump, the plunger g1 of which maybe conveniently operated as shown from the crees-head pin f". g2 is thedelivery valve; g3 the `suction valve and g* the oil supply pipe'.

he compressor 1s arranged tomake its suction stroke just as the periodof maximum compression is being reached in the working cylinder; theairor other `gas from the workingcylinder then passes through the`openings b] of the air and oil nozzle then passes through the smallboretubes e* into the com presser cylinder, being cooled in its passagethrough the tubesto a temperature which may be as low as that of theatmosphere. The compressor `is arranged to make its working stroke atthe point in the cycle at which it is desired to introduce oil fuel intothe Working cylinder, and the pump G makes its Working strokesimultaneously; the result is'that air from the compressor F is forcedthrough the small bore tubes e'* into the atomizing chamber D at thesame time that theoil is forced through the fuel nozzle C into thischamber; the holes c1 in the fuel nozzle are4 arranged to be oppositethe ends of the tubes eA1 so that the air or other gas impinges on theJet of fuel, completely atomizing it, the said air` and oil being oneend communicates With the compressor cylinder through the ports e11 inthe plug @12, the other end of the annular space regarded as apassage-Way is controlled by a valve II fitting` a seating al on thestalkA es.

Vhen the compressor makes its suction stroke the hot gas for the workingcylinder' passes to the compressor cylinder through the small bore tubese", being prevented from passing through the annular space elO by theclosing of the valve Il; When, however, the compressor makes itscompression stroke the compressed gas, on being forced to the fuelinlet, passes through the annular space c as Well as through lthe smallbore tubes et In other .respects the construction and action :is similarto that already described. y

Referring now to Figs. 3 to 5, instead of forming the heat transmittingsurfaces of small bore tubes as described, these surfaces are, in thismodification formed of concentric tubes e13 and em, so arranged as toform an annular passagesvay cli for the gases.

rIhe connection between the compressor and the annular space between thetubes el and el* is made by passage-Way e (see Fig. 4), and the lowerend of the said annular space opens into the atomizing chamber D.

The circulating Water is led through the space e1G round the outer tubeand through the space e Within the inner tube, so that the surfaces ofthese tubes are cooled by the circulating Water which enters at theinlet e, (Fig. 4) thence through the ports e and elo through the spacese1G and 01T, through the ports 620 and e to the outlet egg, and thenceto the Water jacket of the compressor as already described.

The construction and action of the cooler is similar in other respectsto that already described.

Referring now to Fig. (5, the cooler E consists of a small bore spiraltube arranged in the water-jacket space of the Working cylinder. rIheone end of the tube F/ is connected by the union lol to a port a in theWall of the working cylinder, and the other 'end is connected by a unionla: to a fitting O,

provided with a non-return valve ol and a discharge 02 leading to areceiver, said receiver being fitted with a compressor adapted toWithdraw the compressed air or other gas from the receiver and todeliver it to the fuel inlet of the Working cylinder. The said air orother gas and the fuel are sin'uiltaneousl y delivered to the atomiaingchamber arranged substantially as described in reference to theatomizing chamber II in the previous figures,

Referring now to Fig. 7 g-the construc tion of the cooler E and thefitting of it to the Working cylinder A are substantially as describedin reference to Fig. l; the compressor F is, however, arranged With itsaxis at right angles to the axis of the cooler and in this modificationthe compressor is of the opposed-piston type. The air or other gas fromthe working cylinder is, as the pistons f" and f1 move out, drawn fromthe Working cylinder through the cooler E, and into the compressorcylinder through the central port 'S; when the pistons f" and floapproach, the hot air or other gas is driven back through the coolerinto the atomizing chamber I) where it meets with the oil fuel suppliedfrom the nozzle C, the oil and air or other gas being forced into theVworking cylinder through the nozzle B. j

Both pistons of the compressor may be adapted to be reciprocated as inFig. 7; or one only of them may be reciprocated, the other being heldaxially fixed by say, linked attachment to the main frame; by this meansthe compressor cylinder and the means by which it is attached to theworking cylinder are relieved from the unbalanced force'to which theseparts are subjected when the single piston type of cmnpressor isemployed.

The arrangement shown in Fig. 7, is particularly suitable forapplication to engines of the Fullagar type, the pistons f9 and flobeing reciprocated by levers fm, and con-V necting rods fl having balland socket attachments to the pistons, the levers f being reciprocatedin any convenient manner, say by the cam surfaces.

A fuel oil pump arranged substantially in the manner described inconnection with Fig. I is fitted and makes its Working strokesimultaneously with the compression stroke of the compressor.

Obviously the inlet e3 of Fig. 7 may be connected to a fuel pump theplunger of which may in turn be connected to the compressor piston, allof which is of ordinary construction. It will also be obvious that thefitting shown in Fig. 2 may be usedy With the device of Fig. 7.

Having now particularly described and ascertained the nature of my 'saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is l. In an apparatus of the type described the combinationof, the working cylinder; fuel injection opening in the Wall of thecompression space of the saidcylinder; a compressor; a conduit throughwhich the compression space of the compressor is always in communicationwith the said opening, so that the gas partly compressed in the Workingcylinder passes from the latter to the compressor through the conduit,the said gas after further compression in the compressor passing backthrough the conduit to the working cylinder; and means for cooling thesaid conduit; substantially as described.

2. In an apparatus ofthe type described the combination of, the Workingcylinder;

Leashes" a fuel "injection" `opening in the wall ofthe said cylinder; awater jacket for the workj ing cylinder; means for circulating waterthrough'the said jacket; ancompressor; a conduit located in a casingcommunicating with the said jacket through 'which conduit thecompression.spaceof the compressor is always `in communication with thesaid opening, so that the gas partly compressed in the working cylinderpasses from the latter tothe compressor' through the conduit, the saidgas after further compression in the compressor passing back through theconduit to the working cylinder; substantially as described.

3. In an apparatus of the type described the combination of, the workingcylinder; a fuel injection opening in the lWall of the compression spaceof the said cylinder; a compressor; a conduit through which thecompression space of the compressor is always in communication with thesaid opening, through which conduit the gas partly compressed in theworking cylinder passes from theV latter to the compressor and throughwhich conduit the said gas after further compression in the compressorpasses back to the working cylinder; means for cooling the said conduit;a supply of fuel; and a pump for delivering the fuel to the stream ofgas passing from the com-l pressor to the working cylinder;substantially as described.

4.-. In an apparatus of the type described, the combination of.a workingcylinder; a fuel injection opening in the wall of the said cylinder; acompressor; a conduit connecting the compression space of the compressorto the said opening through which conduit the said space is always incommunication with the said opening; a casing connecting the compressorto the working cylinder and enclosing the said conduit; and means forcirculating cooling water through the said casing; substantially asdescribed.

5. In an apparatus of the type described, the combination of a workingcylinder; a fuel injection nozzle assing through the wall of the saidcylinder; a compressor; a conduit connecting the compression space ofthe compressor to the interior of the fuel injection nozzle throughwhich conduit the said space is always in communication with theinterior of the said nozzle; a casing connecting the compressor to thefuel nozzle and enclosing the said conduit; and means for circulatingcooling water through the said casing; substantially as described.

6 In an apparatus of thetype described, the combination of a Workingcylinder; a fuel injection nozzle passing through the wall of theworking cylinder; a conduit con necting the compression space of thecompressor to the bore of the fuel injection nozzle; a casing connectingthe compressor to thefuel nozzle and enclosing the conduit; means forcirculating cooling'water through the said casing; a central stalk inthe casing;

a passageway in the central stalk; a fuel spraying nozzle on the end ofthe said pas sageway adjacent to the fuel injection noz zle; and al fuelsupply connected to theother end vof. the said as described.

7. In combination with the elements of claim 6, a fuel supply pumpdelivering to the said passageway,the plunger of which is connected tothe plunger of the compressor so that they make their workin@r strokestogether; substantially as described.

8. In apparatus of the type described the combination of, a workingcylinder; a water jacket for the said cylinder; an openendedcompartment. extending across the water jacket; `a fuel injection nozzlelocated in the `v'said compartment and passing through the wall of thesaid cylinder; a compressor; a water jacket for the compressor; a casingfitting the said compartment and connecting the compressor to theinterior of the fuel injection nozzle; a conduit extending through thecasing and connecting the compression space of the compressor to theinterior of the fuel injection nozzle; openings connecting the interiorof the casing to the water jacket and a conduit con necting the interiorof the casing to the water jacket of the compressor; substantially asdescribed.

9. In combination with the elements claimed in claim 8, a passagewayextending through the casing; a fuel spraying nozzle fitted to one endof the said passageway near the fuel inlet nozzle; a fuel pumpdelivering to the said passageway, the plunger of the pump beingconnected to the plunger of the compressor so that they make theirworking strokes together; substantially as described.

l0. In apparatus as claimed in claim 3, a second conduit in parallelwith the first conduit tointermittently allow passage of gastherethrough and means to close said con` duit.

11. In apparatus as claimed in claim 3, connecting the plunger of thefuel pump to the plunger of the compressor so that fuel is delivered tothe compressor as the compres` sor piston is making its Working stroke.

12. In apparatus of the type described, the combination of a workingcylinder; a fuel injection nozzle passing through the wall of theWorking cylinder; a compressor having a compression space, a pluralityof conduits connecting the compression space of the compressor to thebore of the fuel injection nozzle; a casing connecting the compressor tothe fuel injection nozzle and enclosing the said conduits; means forcirpassageway; substantially `loo ing; a central stalk arranged in thesaid casing having a. flanged end fitting and enclosing the boi'e of thefuel injection nozzl(` and through which flange the said conduits pass;a passageway in the central stalk; a fuel supply connected to the inletend of the said passageway; a fuel spraying nozzle on the outlet end ofthe said passageway and located in the said enclosed bore of the fue] Yinjection nozzle so as to form an annular space between the nozzle andthe said bore,

through which space the gases from the said conduits flow as they passto the Working cylinder; substantially as described.

In Witness whereof I set my hand.

DAVID MCCRORIE SHANNON.

